Alternating-current relay



April 8, 1930. V. P THORP 1,753,256

ALTERNATING CURRENT RELAY Filed Feb. 1e, 1924,A

5\/ f r 15 Yum@ nnnn INVENTOR 'ATTORNEY Patented Apr. 8, 1930 lUNITED STATES PATENT oFFicE VAUGHN I. THOR?, OF RIVEREDGE, NEW JERSEY, ASSIGNOR T0 AMERICAN TELEPHONE AND TELEGBAPH COMPANY, A CORPORATION 0F NEW YORK .ALTERNATING-CURRENT RELAY cies. Another object is to provide a relay thatshall require simplified circuits, for its operation and a consequent reduction' in its cost and maintenance. objects of the invention will .be apparent from the following description, when read in i connection` with the attached drawing, in which one embodiment thereof is illustrated.

In the drawing, the numeral 5 represents a yoke divided in halves and having a rectangular portion 6 extending" therefrom. The portion 6 may be integral with the portion 5 or may be joined thereto in magnetic connection in such manner as to eliminate airigaps so that magnetic losses are prevented. The members 5 and 6, which are shown in vertical section, are preferably composed of silicon steel or other material having low hysteresis loss and low residual magnetism. Said members may be mounted in anysuitable'manner upon a base with fibre or other non-conductor interposed to provide proper insulation. The armature 7, which may also be composed of silicon steel, is shown as being pivoted at its center and positioned centrally of the halves of yoke 5 and having one end extending up- Wardly from said yoke. Although the armature 7 is indicated as centrally pivoted, it may.

be equally well mounted at its lower end, and in either position it is adapted to vibrate under the attraction of the poles of the yoke so as to make contact with the points 8 and 9, to which are connected the conductors 1() and 11, respectively, which may be associated with local circuits.

A coil 12 is shown as encircling the armature 7 and in practice this may be in the formI of a spool, in the center of which said ar1nature is positioned. The ends of the coil 12 are connected to conductors 13, which extend to an outgoing line. For the purpose of bias- These objects and further.v

ing diaphragm 7, a coil 14; surrounding said armature and a coil 15 surrounding one side of the portion 6 of yoke .5 are connected in lseries with conductors 16, which extend to a sourcew of direct current. On the lower arm ofthe member 6, a coil 17 is provided and connected to conductors which lead to a local source of alternating current for the purpose to be presently described. l

In the operation of the improved arrangementa high frequency or alternating current incoming over the line conductors 13 flows in the coil 12, surrounding the pivoted armature 7, 'and sets up a magnetic field therein. The operating flux produced will divide equally at the ends ofthe armature 7 and llow around the two halves of the enclosing soft steel yoke 5 in: opposite directions. Alternating current "from a local source Hows over the conductors connected with the coil 17, which surrounds the yoke 6, and produces therein a polarizing flux. This current is in phase with the current from the incoming line over conductors 13.

The polarizing flux created by the iow of alternating current from the local source and the operating flux created by the fiow of' alternating current over the line conductors, produces such reaction in the armature as to cause it to move toward the same contact during both the positive and negative halfcycles of the alternating currentwave. The inertia of the armature is such as to prevent its Aleaving the Contact when the alternating vcurrent 'wave is passing through the Zero point.` Consequently, when a succession of spacing contact by the biasing current from the local direct current source Which Hows through the coils 14 and 15 in series, as illustra-ted.

A spring may also be used,l if dey -sired, to give the desired biasing effect.

What is claimed is:

1. A relay comprising a divided yoke, an extension for magnetically connecting the divided portions ofthe yoke, an armature movably mounted between the divided portions of the yoke, a coil associated with said armature, a second coil associated with saidy extension, means independently associated With each coil for independently impressing thereon polarizing and operating 'currents in phase with each other, and means serially associated with said extension and armature for biasing the armature. n

2. A relayI comprising a divided yoke, an extension for magnetically Vconnecting the divided portions of the yoke, an armature movably mounted between the divided portions of the yoke, a coil associated with said armature, a second coil associated With said extension, and an independent source of alternating current connected with each' coil, the currents from each source being of like phase for producing such reaction in tlie armature as to cause it to move in the same direction during both the positive and negative half cycles of alternating current Wave.

3. A relay comprising a divided yokean extension for ymagnetically connecting the divided` portions of the yoke, an armature movably mounted between the divided portions of the yoke, a coil associated with said armature, a second coil associated vWith said `extensioman independent source of alternating current connected independently With eacli coil, the currents from each source being of like phase for producing such reaction in the armature as to cause it to move in the same direction during both the positive and negative half cycles of alternating current Wave, and means serially associated in circuit with said extension and armature for biasing said armature.

4. A relay comprising a divided yoke, an extension for magnetically connecting the divided portions of the yoke, an armature movably mounted between the portions of the yoke, a. coil associated With the said eXtension, a second coil associated With said eX- tension, means independently associated With each coil for independently impressing thereon alternating currents in pbase With each other for creating an operating flux and a polarizing iiux in said yoke and armature, said fluxes coacting to cause said armature to move in the same direction during both the positive and negative half cycles of alternating current Wave, and means serially. connected in circuit'with said extension and armature lfor biasing said armature to its spacing contact.

In testimony whereof, I have signed my name to this specification this 15th day of' February, 1924.

VAUGHN P. THORP. 

